I consistently observe sleep is non-negotiable. Sleep is easily as important as keto itself, but I meet so many people IRL and online who speak as if sleep is an afterthought. I am a TOTALLY different person based on 4, 6, 8, 10 hours of sleep or not. On 4 hrs sleep for 3 days, I pretty much can't exercise (lethargy), can't tolerate cold therapy (because of rT3), constantly hungry no matter how much or what I eat, it's just a total MESS. Source by susanmcgarvey